Automatic machine gun



July'1, 1924. 1,499,846 Q G. H. TANSLEY ET AL AUTOMATIC MACHINE GUNFiled Sept. 24 1923 2 szmLs-srm; 1

Jul 'l 1924. 1,499,846

G. H. TANSLEY ET AL AUTOMATIC MACHINE GUN Filed Spt. 24, 1923 2Sheets-Sheet 2 I 4 ,gui

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* UNITED STATES 1,499,846 1 PATENT OFFICE. I

GEORGE H. TANSLEY AND CHRISTIAN PFEIFFER, OF HARTFORD, CONNECTICUT, AS-

SIGNORS TO COLTS PATENT FIRE ARMS IVIANUFACT'URING COMPANY, OFHABT-' 7FORD, CONNECTICUT, COBPOB-ATIGN OFCONNEGTICUT.

'Arr'roMArIc MAGHINE Gun;

Application filed September '24, 1923. Serial No. 664,465.

erence being had to the accompanying drawings, forming a part hereof.

' The invention relates generally to automatic machine guns of thatclass in which the heavy recoiling parts, such as the barrel and barrelextensiorn'are brought to rest gradually and without injurious shocksor. stresses, by some-form of butter located within the breech casing,such as a liquid lender or brake acting in the manner of a dash pot, forexample, which buffer is made adjustable to vary its action under thevarious conditions of operation to which such guns are liable. r

The invention relates particularly. to such guns in which the adjustablebuii'er rests against the rear wall of the breech casing, and in whichsaid rear wall comprises a plate transversely removable from the easingto permitfwithdrawal and inspect-ion 1 of the mechanism within saidcasing. 3 It is an object of theinvention to provide easily accessiblemeans, preferably carried by the rear plate, for adjustingthe butterlocated within the breech casing of the gun without opening said casing,together with means for indicating the amount of such adjustment'ontheoutside ofthe casing. A further object of the invention is theprovision of deviceswhereby,inthe removal of the rear plate, theadjusting and indicating means-carried by said rear plate isautomatically disengaged from itsoperative relation with the buffer,thereby allowing ofa rapid and-easy removal of said rear plate and theparts carried'thereby from thecasing; it isa further object to providemeans whereby the assemblyot the rear plate and the parts carriedthereby on the casing is facilitated. These objects are attained by thnism illu'stratedin the accompanying drawings, in which: 7 r j r V Fig.1is a rear end vieu ofa machine gun showing the invention appliedthereto;

' mecha- Fig. 2:.isa lett-handjside view-oi the rear portion of the gun,partsbeing. shown in section;

Fig. 3 is a top view of said. rearjportion;

of the gun; 7 V

Fig. 4 is a side elevation of the rear portion of the gun showing thelower portion in a central vertical longitudinal section, the adjustingand indicating means on the rear plate being shown in operativeengagement with the buiier; V

Fig. 5 is a side view similar, to Fig.4,- but showing the latch fortherear plate andlthe adjustlng and indicating means in their in operativeposition, preparatory to; the up ward removal of the rear plate;

Fig. 6 is a horizontal longitudnialsection through the rear portion ofthegunncasing, and through a tubular member therein, with a portion ofthe: bufler tube'broken V away to show the groove in its rear; sectionbeing taken on the line.

wall, the, 66 of Figs. 7, 8 and 9 show thecombined indig eating finger.and adjusting arm, detached,

respectively in a left-hand side view, in a rear view and in a top view;and

Figs. 10, 11 and 12 show the rear plate latch, detached, respectively inaleft-hand 7 side view, in a front view and in atop view.

Similar numerals refer to similar parts throughout the several views.

The breech casing of the gun to whicht-he invention is shown appliedcomprises-the side plates 1, 1, the top plate 2, the bottom plate 3 andthe vertically removable rear plate 4, which is locked in its lowerclosed posit-ion by the latch 5 having a forward projection whichengages under the bottom plate 3. V

The rear plate 4 has at its upper end a forward projection .whichfits inacorresponding recessin the top plate 2, see Fig. 3, and said rear plateis provided with ribs or projections 4 which fit corresponding verticalgrooves in the side plates ot'the casing. Said rear plate is slidupwardly for dismounting and downwardly for mounting it, and is kept inits seat by the latch 5 piv oted on the transverse pin 13 in .the'rearplate and held in its locking position, with the forward projectionthereon engaging projection .5 on said latch limits the lVithin thebreech casing are mounted therecoiling parts of the mechanism (notshown), the recoil of which is cushioned by any suitable form of bufferor brake, such as the liquid buffer represented by the cyglindrical tube8 resting against the rear plate 'ofth'e casingand rotatably mounted inthe tubular member 9 fitting the lower rear port1on of said casing. 7 7

For ad usting said buffer, which may cornprise some form of dash potdevice, such as is fully disclosedfor example in the application of J.M. Browning, Serial Number 654,955, filed July 31', 1923,) the rotatabletube 8 is provided with a transverse groove 8 its integral .rear wall; acorresponding rib lO 'on the forward end of a shaft 10 is adapted toextend into this groove. Said shaft -is mounted in the rear plate andpro-- jects outside said plate at itsrear end, where it is provided witha combined adjusting 1 arm and indicating finger 12, which is connectedwith said shaft by any suitable means, such as a transverse pm.

By this construction it will be obvious that the shaft 10 can be rotatedmanually; to

adjust the rotatable buifer'tube 8 by simply grasping the adjusting arm12 and rotating it the required amount.

In orderto permit the upward removal of the-rear plate 5. it isnecessary to withdraw the rib 10 on the shaft 10 fromthe groove 8 in thebulfertube 8; to allow such withdrawal, the shaft 10 is mounted in therear plate so as to have endwise movement. The shaft is yieldingly heldin its inner operative osition by a spring 11 coiled about it and earingat its forward end against a collar on the shaft, andat its rearendagainst a shoulder on the rear plate, see Figs. 4, and

V 6. By moving the. shaft rearwardly against '7 Byour inventi thetension of the spring 11 to the position shown in Fig. 5, the rear plate4 can beupwardly withdrawn, assuming that the rear plate latch 5 hasbeen disengaged from thebottom plate 3. q

p 7 I on, this rearward movement ofthe shaft is effected automaticallyin theact. of removing-the rear plate. A convenient manner of attainingthis end is 5 to'provide co -operating devices on. said ad ustlngarml2tand the'rear plate latch ,5,

so. that, when the latch 5 is movedrearward to fregfthe forwardprojection thereon from thejbottom plate 3, the adjusting arm '12andthe' connected shaftlO will be simul'- taneously moved. rearward,thereby with- Clrawing'the rib 10 -on the forward end of said shaft fromgro'ove l in the buifer tube.

Such devices may comprise a cam surface 5 on the rear face of the latch5, see Figs. 4 and 10, which surface is in position to engage the lowerslightly rounded edge of a laterally widened sector-shaped forwardportion of the arm 12, said-portionforming wings 12?. see Figs. 8 and 9,projecting at each side of the central knurled portion 12 of the arm,which is adapted to be grasped by the hand ofth'e operator. Said wings12 project laterally a distance sufficient to insure that, in alloperative positions of the adjusting arm 12, some partof the lowerrounded edge of said sector-shaped portion will be located opposite saidlatch 5, where by the cam surface on the latch may engage said roundededge of the arm 1:2 to camit back regardless of the position of adjustment of the parts within their operative limits. i r

The means for indicating the amount of the adjustment of said buffer maycomprise graduations and an index co-operatingwith said graduationsj inthe form of our invention shown, an upward projecting finger 1S2 onthearm IQ'SGI'VQS as an indicating finger and is preferably provided withan 7 index or notch 12 which co-operates with suitable opposed fixedgraduations, see Fig. l, to indicate the amount'of the adjustment.

To remove the rear plate, the operator pulls rearwardly on the fingerpiece 5 of V the rib 10 on said shaft from the groove .8 7

in the buffer tube 8, then the'rear plate may be upwardly withdrawn fromthe casing.

To facilitate the re-assembly of the rear plate, suitable'provision ismade to move the shaftlO rearward automatically during the downwardsliding movement of the rear plate in mounting it; To this end, the up:per edge of the tubular member 9 is rounded over as shown at 9, sothat,'when the rib 10 encounters said rounded edge the rib is cammedback and the downward movement of theplate l is continued, until thebevel on the iuider side of the forward projection 5 of the latch 5engages the bottom plate '3 and automatically moves the latch "rear-Vwardly by beveling the top of the. end of the plate 3 this action isfacilitated; When the plateft and the latch reach the lowest position,the- 'forwardprojection 5 of the latch will reengage the bottom plateunder the action of the spring 14, and at the same time the rib 10 ofthe shaft 10 will under the action of spring'll reenter the groove 8"said casing for rotating saidto ad Lemma in ,thebufiier tube,.-when the-rib and the groove coincide.v .If, howevery the shaft 10 or the tube 8,have been rotated relatively from the position they occupied before theremoval-of the rearplate, thenthe rib 10 and the groove 8 may notextendlength= wise in the same direction when the rear plate is reassembled;by simply rotating the shaft 10 until said rib and said groove againextend in thelsame direction, the rib will be automatically moved intosaid groove by the action ofthe spring 11. V

The adjusting andindicating mechanism mounted on the rear plate, is, forconvenience ofmanufacture, carried by a separate piece i which issecured to the rear plate proper by suitable means, such as the screws7, see Figs. 1 and 2, but it is obvious that this piece 4 might beanintegral part oftherear plate i. 7 While we have herein described indetail aspecific embodiment of our invention, we do not wish to limitourselvesto the particular construction or arrangement of parts shownand described, as'obvious modificationswilloccur to those skilledin theart.

"WhatweZclaim and desire 'to secure by Letters Patent is:

l A machine gun comprising a breech casmghaving a rearplate, arotatably'adjustable 'member resting against said rear plate,- a shaftforadjusting said" member mounted in said rear plate and means forindicatin the amount of. the adjustment associate with said shaft; 1 1 a'2. Al machine gun comprising a breech casing having a rearcplate, arotatably adjustablelbufier member resting against said rear plate and'having a groove in its rear surface, ajshaft -mounted 1n said rearplate andhaving a rib on its forward end extended into' said; groove,and meansutside i shaft and thereby adjustingsaid member; v

A machine gun comprising a breech easing having a transversely removablerear plate, a' rotatablyadjustable bufi'er tube resting against saidrear plate and having a} groove in its rearsurtace, a; rotary memberhaving-a corresponding :rib at'itsiorward end for engagement into saidgroove, said rotary member being mounted in said rear plate, resilientimeans for holding said member in its forward position with its rib engagng said groove,-and-means outside said casing-whereby said member may berotated j stjsaidbufi r tube and moved end wiseifagafins tthe tension oisaid resilient means to withdrawsaid rib from said groove, therebypermitting removalof the V plate when desiredr 4. In amachine gun, thecombination of a breech casing having a transverselyremovable rearplate, an adjustable member inside said casing, and means carried bysaid rear plate and normally: connected with said member for adjustingit, said means being constructed and arranged to be automaticallydisconnected from said adjustable member upon removal of said rearplate.

5. In a machine gun, the combination i a breech casing having atransversely removable rear plate, a rotatably adjustable member in saidcasing and having its rear end resting-against said rear plate, andmeans carried by said rear plate and normally connected with said memberfor adjusting it, said means being constructed and ar ranged to beautomatically disconnected from saidadjustable member upon removal ofsaid rear plate. a

' 6. In a machine gun, the combinationof a breech casing having atransversely removable rear plate, a rotatably adjustable bufler memberin said casing and resting against said rear plate, means carried bysaid rear plate and normally operatively connected withsaid-member foradjusting it, a latch for locking said rear plate in assembled position,and devices whereby the movement of said latch to release the rear plateautomatically disconnects said member and said means to permit withdrawal of the rear plate from the casin T.- In a machine gun,thecombination ofa breech casing having a transversely removable rearplate, a longitudinally'extending member adapted 'to be rotatablyadjusted and resting against said rear plate, means carried by said rearplate and normally in operative engagement with said member foradjusting the same, and means for automatically breaking said operativeengagement upon removal of the'rear platecomprising a device for lockingsaid rear platein its assembled position. 7 is V 7 '8. In a machine gun,the combination oi abreech casing having a transversely removable rearplate, a rotatably adjustable member} in said casing and resting againstsaid rear plate, said member. having a groove in its rear surface, arotary deviee carried-by said rear plate and having a rib at its forwardend entering said groove whereby rotation of said device causescorresponding rotation of said member, and means for automaticallywithdrawing said rib from said groove in the removal of said rear platefrom the casing. a V

9; In a machine gun, the combination of a breech casing havingatransversely remov-c V ,ing a rib 10. In a machine gun, the combinationof a breech casing having a transversely removable rear plate, a latchpivotally'mounted in said rear plate for holding the same in itsassembled position, a rotatably adjustable member in said casing andresting against said rear plate, said member having a groove in its rearsurface, a rotary shaft carried by said rear plate and havmgacorresponding projection at its forward end extending into said groove,said shaft having also an endwise movement, and means whereby themovement of the latch to 'release said rear plate automatically movessaid shaft endwise to withdraw said projection from said groove,-thereby' faclhtat ing the removal of the rear plate.

11. In a machine gun, the combination of a breech casing having'a'transversely removable rear plate, a latch carried by said rear platefor locking it in assembled position. a rotatably adjustable member insaid casing and resting against said rear plate, a rotary shaft carriedby said rear plate and operatively connected Wlth said ad ustablemember, said shaft having also an endwise movement to break saidconnection, a sector shaped arm secured to said" shaft, said arm andsaid latch having co-operative cam surfaces,'whereby movement of thelatch to release the rear plate automatically moves said shaft'endwiseto break said connection for all operative positions of said arm.

12. In a machine gun, the combmation of a. breech casing having 'atransversely removable rear plate, a latch for locking said rear platein assembled position, a rotatably adjustable member in said'casing andresting against said rear. plate, said member having a groove in itsrear surface, a shaft carried by said rear plate'and havin its forwardend entered into said groove whereby rotation of the shaft causesrotation of said member, said shaft also having endwise movement towithdraw said rib from said groove, an arm secured to said shaftcarrying an arcuate cam surface, and a cam surface on said latch forco-operation with said arcuate cam surface in any operative'position ofsaid arm, whereby 'movement of the latch to release said rear plateautomatically moves said shaft endwise for withdrawing said rib fromsaid groove. 13. Ina machine gun, the combination of a breech casinghaving a transverselyre i,

movable rear plate, a latch for'locking said rear plate in assembledposition, a rotatably' r adjustable member in said casing and restingagainst said rear plate, combinedadjusb,

ing and indicating means operatively' con? nected with said memberlandconstructed and arranged to be automatically discon nected therefromupon the movement of said latch to release said rear plate.

" 14. In a machine gun, the combination of combined adjusting andindicating arm secured to said shaft, and aconnection between said armand said latch whereby the shaft is moved endwise to withdraw said ribfrom said groove when the latch is moved to release the rear plate. 7

15. In a machine gun, the combination'of a breech casing, having atransversely. re

movable rear plate, an adjustable member resting against said rearplate, means carried by said rear plate for'adjusting said memberfrom'the outside of the casing, and

plate, said adjusting means isautomatica'lly moved to disengage itfromvsaid member,

and means permitting the automatic re-engagement of said parts upon'th'ere-assembly of said rear plate. 1 1 a 16. In a machine gun,thecombination of a breech casing having a"tra'nsv'ersely removable rearplate, an adjustable. member resting against said rear plate and havingmeans whereby in the removal 'ofsaid rear a groove in its rear surface,a shaft carried by said'rear plate, said shaft being yield i 7 inglyheld in a forward position with a rib thereon extending" into saidgroove, and

means whereby, upon the removal of the rear plate, said shaft isautomatically moved endwise to withdraw said rib from" said groove, andmeans whereby said shaft'is automatically moved rearwardly to allow thefull insertion of said rear plate in its seat in the casing andto'permit theauto- 'matic re-engagement of said rib and said a Thisspecification signed and witnessed groove. I

of September, AID. 192? GEORGE H; TANSLEY." V CHRISTIAN PFEIFFERf In thepresence of MOLLIE A. ONnnt, f J. C ALVIN BRIGHT;

this l lth day

